1. Field of the Invention
The present invention relates generally to factory systems and, more particularly, to implementing changes to the manufacturing process simply and efficiently.
2. Description of the Related Art
Technological advances have produced increasingly complex manufacturing systems. For example, manufacturing of integrated circuits is perhaps the most complex manufacturing process in existence today. Factors contributing to this complexity include constant device miniaturization, process intricacy, product diversity, and changing technologies. Management of the semiconductor manufacturing process is accordingly complex and can involve planning thousands of steps to be performed on a silicon wafer to produce a fully packaged and integrated electronic component.
In most factories, it is desirable to have a single system that controls product flow and equipment usage. Such a system is referred to herein as a factory system. A factory system manages the manufacturing process for a product by controlling a route of operations to be performed by various manufacturing tools in the factory to produce the product. Different manufacturing tools may be used in each operation, multiple manufacturing tools may work together to perform a single operation, and a tool may be used at more than one stage of a single operation.
Various types of information relate to the manufacturing operations performed in the factory. Often the information for performing a manufacturing process is maintained as documents or files, which are referred to herein as configuration documents. For example, a type of configuration document is a specification document that specifies the manufacturing processes to create a particular layer on a wafer in manufacturing a particular semiconductor chip. Typically, a specification document is a file that is read by an equipment interface, which is a software application running on a dedicated computer system that controls a manufacturing tool. Because various tools can be involved in a single operation, the equipment interface for each tool must have access to an identical copy of the specification document.
In a semiconductor factory, losing even a few minutes of operation of a single tool is extremely expensive. Accordingly, changes to configuration documents, such as specification documents and recipes, are avoided, and typically very few people are authorized to make such a change. When such changes must occur, the changes are tested rigorously and subject to an extensive approval process, because of the cascading effects of a single change.
In a typical semiconductor manufacturing facility, the specification document includes a recipe for each manufacturing tool involved in the operation. A recipe is a set of instructions that causes a tool to perform a particular operation on the silicon wafer. As an example, in an etching manufacturing process, an etcher manufacturing tool etches silicon from a wafer. A recipe for a particular operation on the etcher causes the etcher to remove a certain thickness of silicon from the wafer in a particular pattern. Different recipes may apply when manufacturing different products or at different stages in the manufacture of a particular product. The specification document typically includes a separate recipe defined for each possible context in which the etching manufacturing process might be used, thereby duplicating the recipe information numerous times.
An alternative implementation is to provide a single recipe document that contains information about which operations at particular tools in the factory use the recipe.
Problems with the typical implementations described above arise when the manufacture of a product changes or a tool becomes involved in new or different operations. For example, assume that a recipe for etching a particular layer of a particular chip changes. In the first implementation described above, it is necessary to modify the specification documents for each manufacturing tool in the factory that performs the related operation, a time-consuming and error-prone process that is becoming unacceptable in today""s 24xc3x977 factory environments.
In the second implementation, it is necessary to change the recipe document each time an operation using the recipe changes, which may be frequent as tools are added and switched to perform different operations.
What is needed is a way to isolate the information related to performing a manufacturing process from the context in which the information is to be used. It is desirable to enable a change to a context and/or a configuration document to be made without affecting numerous tools and operations. Preferably, such a change can be made without requiring such an extensive management review and approval process.
The present invention provides a way to isolate information related to performing a manufacturing process, called a configuration document, from the context in which the information is used. The process context can be defined, and context-specific information can be removed from the configuration document to create a context-free configuration document. A context/configuration association is independently established between the process context and the context-free configuration document. Because the context/configuration association is independent of both the process context and the context-free configuration document, the context/configuration association can be independently reviewed and approved without affecting other process contexts or configuration documents.
One form of the invention includes a method including specifying a context/configuration association between a context-free configuration document for the manufacturing process and a process context and activating the context/configuration association to implement a change to the manufacturing process. The method may further include approving the context/configuration association prior to the activating the context/configuration association.
In another form of the invention, an apparatus includes an association module to specify a context/configuration association between a context-free configuration document for a manufacturing process and a process context and an activation module to activate the context/configuration association to implement a change to the manufacturing process. The apparatus may further include an approval module to approve the context/configuration association prior to activating the context/configuration association.
The foregoing is a summary and thus contains, by necessity, simplifications, generalizations and omissions of detail; consequently, those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the present invention, as defined solely by the claims, will become apparent in the non-limiting detailed description set forth below.